Abstract:

BACKGROUND: Due to the excellent activity, metal-on-metal total hip prosthesis has been widely used in artificial total hip replacement.
OBJECTIVE: To investigate the medium and long term effect of metal-on-metal large diameter total hip replacement．
METHODS: From April 2004 to June 2005, 21 hips of middle-aged and young patients were underwent the metal-on-metal large diameter total hip replacement under combined spinal-epidural anesthesia, and followed-up by the same surgeon through outpatient reexamination, telephone, mail letter, and statistics ipsilateral hip Harris score, range of motion and the occurrence of complications at 5 years postoperative.
RESULTS AND CONCLUSION: The average Harris hip score is (94.3±1.6), the flexion angle was(111.2±14.3)°, abduction angle was (40.3±3.4)°,adduction angles was (23.5±2.4)°, external rotation angle was (54.8±3.7)°, Internal rotation angle was (20.9±2.1)°, no dislocation was observed, 1 hip showed mild osteolysis (4.8%), 2 hips appear implant loosening, 2 hips appear painful around the hip joint at 5 years follow-up postoperative. And all these complications appeared at the 6th month after replacement and maintained for 5 years. Metal-on-metal large diameter total hip replacement showed good medium-term stability and joint function recovery, and low pain incidence. Especially for young patients, it has good clinical application value.